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MD9.6 Release: Highlights. Increased the character limit for all URL resources to 600 characters. Data_Center/Service_Provider Data_Set_Citation/Service_Citation Multimedia_Sample Related_URL Developed second level for Related_URL Content Type
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MD9.6 Release: Highlights • Increased the character limit for all URL resources to 600 characters. • Data_Center/Service_Provider • Data_Set_Citation/Service_Citation • Multimedia_Sample • Related_URL • Developed second level for Related_URL Content Type • The two-level hierarchy is available with a set of controlled keywords. GET DATA > THREDDS DATA GET DATA > THREDDS DIRECTORY GET DATA > WHOM GET DATA > WIST
MD9.6 Release: Highlights Cont.Relative Time Capability for data sets • Accommodate data “pools” where current data are offered for specified periods and rotated as temporal subsets. • How it works: • Enter in DIF: <Keyword>RELATIVE_START_DATE: -7</Keyword> • Nightly cron is run to update the production database (convert_relative_start_date.pl) • End user sees: <Temporal_Coverage> <Start_Date>2006-09-06</Start_Date> <Stop_Date>2006-09-13</Stop_Date> </Temporal_Coverage>
MD9.6 Release: Highlights Cont.Relative Time Capability for data sets • Stipulations • There is only one RELATIVE_START_DATE value per DIF • STOP_DATE is always today • The relative date must be negative • An initial Temporal_Coverage group (START/STOP DATE) must be pre-populated in the DIF • Next generation will be in the Java code w/o these stipulations
DIF Example Relative-Time captures Current date and automatically populates Temporal_Coverage field
MD9.7 Projected Release • Home Page/Metadata display enhancements in response to usability testing and analysis of user statistics. • Usability testing unearths aspects overlooked as site develops and user expertise advances. • Analysis of statistics guides our understanding of how the site is being used.
MD9.7 Projected Release Cont. • Send automated update reminders to metadata authors. • Create XML namespace • To provide compliance with Open Archive Initiative (OAI) - Protocol for Metadata Harvesting (PMH). • Upgrade taxonomies to extend logical patterns of understanding for search and retrieval. • Platforms/Instruments
Future Releases • Continue upgrading taxonomies to extend logical patterns of understanding for search and retrieval. • Science Keywords • Locations • Chronostratigraphic Units • Create a repository for very small Datasets • Prepare for Intergovernmental Panel on Climate Change Assessment Report (IPCC AR4/5) • Accommodate enhanced descriptions of model output data through an extension.
Future Releases • Incorporate Service Oriented Architecture to enhance interoperability among data and service providers, using widely accepted standards. • Rewrite MD Server using Semantic Service Oriented Architecture. • Rewrite Operations (OPS). • Provide UDDI Registry for Services. • Implement RDF and SKOS to incorporate ontologies.
What is SKOS? • Simple Knowledge Organisation System(s) • SKOS Core • http://www.w3.org/2004/02/skos/core/ • Goal: Simple, flexible, extensible, machine-understandable representation for… • Thesauri • Classification Schemes • Taxonomies • Subject Headings • Other types of ‘controlled vocabulary’…
SKOS Basics • SKOS Core is an application of the Resource Description Framework • RDFS Classes and RDF Properties • Use it to describe Concepts and Concept Schemes RDF is based on the idea of identifying things using Web identifiers (called Uniform Resource Identifiers, or URIs), and describing resources in terms of simple properties and property values. This enables RDF to represent simple statements about resources as a graph of nodes and arcs representing the resources, and their properties and values.
SKOS Essentials • Basic Structure skos:Concept • Lexical Labeling skos:prefLabel, skos:altLabel,skos:hiddenLabel • Symbolic Labeling skos:prefSymbol, skos:altSymbol • Documentation skos:definition, skos:note, skos:example, etc. • Semantic Relations skos:broader, skos:narrower,skos:related
SKOS Property: BROADER/Narrower Relationships . ‘Hydrosphere’ ‘Ground Water’ ‘Ground Water Discharge/Flow’ skos:prefLabel skos:prefLabel skos:prefLabel skos:narrower skos:narrower GROUND WATER HYDROSPHERE GROUND WATER DISCHARGE/FLOW skos:broader skos:broader <rdf:RDF <skos:Concept rdf:about="http://www.example.com/concepts#ground_water_discharge_flow"> <skos:prefLabel>Ground Water Discharge/Flow</skos:prefLabel> <skos:broader rdf:resource="http://www.example.com/concepts#ground_water"/> </skos:Concept> <skos:Concept rdf:about="http://www.example.com/concepts#ground_water"> <skos:prefLabel>Ground Water</skos:prefLabel> <skos:broader rdf:resource="http://www.example.com/concepts#hydrosphere"/> <skos:narrower rdf:resource="http://www.example.com/concepts#ground_water_discharge_flow"/> </skos:Concept> <skos:Concept rdf:about="http://www.example.com/concepts#hydrosphere"> <skos:prefLabel>Hydrosphere</skos:prefLabel> <skos:narrower rdf:resource="http://www.example.com/concepts#ground_waterr"/> </skos:Concept> </rdf:RDF>
Subject Indexing (Science Keywords) <?xml version="1.0" encoding="UTF-8"?> <rdf:RDF xml:base="http://gcmd.gsfc.nasa.gov/skos/parameters.rdf" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:skos="http://www.w3.org/2004/02/skos/core#"> <skos:Concept rdf:about="#EARTH SCIENCE|HYDROSPHERE|GROUND WATER|GROUND WATER DISCHARGE/FLOW"> <skos:prefLabel>GROUND WATER DISCHARGE/FLOW</skos:prefLabel> <skos:definition>Pertaining to the amount of water traveling through an aquifer, or aquifer system, measured in units of volume per units of time.Reference: Goudie, Andrew. 1997. The Encyclopedic Dictionary of Physical Geography. Blackwell Publishing, Malden, Massachusetts. </skos:definition> <skos:broader rdf:resource="#EARTH SCIENCE|HYDROSPHERE|GROUND WATER"/> <skos:isSubjectOf rdf:resource="http://gcmd.gsfc.nasa.gov/getdif.htm?USGS_OFR_2006_1171_PG_SJCC"/> <skos:isSubjectOf rdf:resource="http://gcmd.gsfc.nasa.gov/getdif.htm?USGS_OFR_2006_1084_EBP_AC_CA"/> <skos:isSubjectOf rdf:resource="http://gcmd.gsfc.nasa.gov/getdif.htm?CIESIN0178"/> <skos:isSubjectOf rdf:resource="http://gcmd.gsfc.nasa.gov/getdif.htm?USGS_OFR_2006_1129_WIPP_NM"/> … </skos:Concept> </rdf>